After my visit of the Japanday 2018 in Düsseldorf I want to explain how I made these firework shots and why I could enjoy the fireworks despite taking pictures. The technic I explain in this blog post is also useful to capture lightnings.
The problem with lightning and firework shoots is always if you hear it you are to late. So what about make a video. Yes this is possible but if you try to extract a single frame from the video after it won't have the trails from the light and its not as sharp as it would be if it is a single image. So what can we do to achieve nice and sharp images?

Firework at Japanday 2018 in Düsseldorf Shot on Sony a7R III with the Sony FE 24-70mm f/2.8 GM Settings: 2.5" / f8 / ISO100 / 28mm — Firework at Japanday 2018 in Düsseldorf
Shot on Sony a7R III with the Sony FE 24-70mm f/2.8 GM
Settings: 2.5" / f8 / ISO100 / 28mm

Preparentation
First of all you need a tripod which can support you camera weight and is steady enough if there is wind. For this particular shoot I used my Rollei Rock Solid Gamma Carbon Tripod with the Manfrotto MHXPRO BHQ6 XPRO. You also need an intervalometer for your camera as well as a fast lens which was in my case the Sony FE 24-70mm f/2.8 GM.

After that you have to check where the action will happen and keep in mind that the firework will be high in the sky so you have to aim your camera a little bit higher. Depending on your location and distance to the firework you have to use wider lens so you can capture the ground as well as the big fireworks high up.

Settings
The settings depend alot on the environment and the effect you want to achieve. The two main parts here are that you have to shoot in full manual mode and use manual focus as you don't have the time to focus. Also you have to disable long exposure noise reduction because this will double your exposure time. With full manual mode a good starting point is a shutter speed of about 2.5 sec (why this special number? I will explain it in the next section). Your ISO should be as low as possible I use here when ever possible ISO 100. As I expect some really bright fireworks I used a apature of f8. If the firework starts and you see that your images are blown your go up with your apature or lower you shutter speed.

How to catch 'em all
The easiest way to capture every exploding firework or every lightning just make a timelapse of it (Timelapse Cheatsheet). And here its important to choose the correct interval. In the last section we used a shutter speed of 2.5 sec and this gets important here. Depending on the buffer clear speed and shutter lag of your camera you can choose an interval as close as possible to your shutter speed. My Sony a7r III has a buffer clear speed of 0.3 sec and a shutter lag in manual/prefocused of 0.023 sec which results in about 0.32 sec of processing time after every image. Depending on this I used an interval of 3 sec so that my camera have enouth time to clear the buffer. The result is that I have coverage of 83% of the complete firework. Possible whould be a converage of about 89% with the risk of loosing some release.
There is also the possibility to use a lightning trigger to capture the firework. But please keep in mind that you may have the problem that the trigger doesn't trigger in time or triggers too often.

Conclusion
I alsways use this technic to capture fireworks because after I setted it up and started the timelapse I can enjoy the firework by my self and not through the Viewfinder. And in addition I can also render a nice timelapse of the complete timelapse. If you have any questions just leave a comment :)